The Coordinate Plane or the (X, Y) Coordinate Plane is nothing more than two intersecting number lines.

The Horizontal Line is usually called the 'X' coordinate or the Domain or the Input.

The Vertical Line is usually called the 'Y' coordinate or the Range or the Output.

Be careful to watch the UNITS or scale on the graphs (it is not always '1')

The Point: (0, 0) is called the ORIGIN.
There are FOUR quadrants given the Names with Roman Numerals: I, II, III, and IV

Quadrant I: Top Right (+X, +Y)
Quadrant II: Top Left (-X, +Y)
Quadrant III: Bottom Left: (-X, -Y)
Quadrant IV: Bottom Right (+X, -Y)
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Coordinate Plane
X-Axis (Horizontal)
Y Axis (Vertical)
Origin (0,0) where x and y axes cross
Ordered Pair (x, y) identifies a location on the coordinate Plane
Quadrants: I. (+ +)   II. (-, +)  III. (-,-)    IV. (+, -)


Distance | x2 - x1| or |y2 - y1|
OR Add values when you cross Quadrants:  |x2| + |x1| or |y2| + |y1|
Subtract when you are WITHIN a quadrant: |x2| - |x1| or |y2 |- |y1|

When you cross an Axis, one of the signs will be Negative, So: x2 - (-x1) -> (x2 + x1) 
Distance is not (-) negative so the Absolute Value | q | is used.

REFLECTION:
Over X:   (x, y) Becomes (x, -y)
Over Y:   (x, y) Becomes (-x, y)
Over both (X, Y):       (x, y) Becomes (-x, - y)

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Never Eat Sea Weed
NORTH = UP  + Y
EAST = RIGHT + X
SOUTH = DOWN ( - Y)
WEST = LEFT ( - X)




Worksheets: https://www.dadsworksheets.com/printables/coordinate-plane-quadrant-labels.html

https://sites.google.com/a/lsr7.net/wve-math/teachers/6th-grade-resources/6th-grade---unit-4---coordinate-plane
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https://www.helpteaching.com/questions/Coordinate_Geometry/Grade_6

Revised: May 1, 2024